The Mercedes GL 450 CDI 306hp (X164 - 2006 - 2012) produces 306bhp and 700Nm in standard form. Our Stage 1 ECU tuning file raises output to 350bhp and 810Nm, a gain of 44bhp and 110Nm, with no hardware modifications required. The file is delivered through the ByteFLASH portal and is ready to write to the vehicle.